[RESEND PATCH v1 2/2] cmd: ubi: check 'updating' before calling ubi_more_update_data()

[Martin Kurbanov]

If 0 is passed to the 'bytes' parameter in the ubi_start_update(),
there is no need to call the ubi_more_update_data(). Otherwise,
there will be a double-free of 'vol->upd_buf'.

Also check that the ubi_start_update() was called before calling
the ubi_more_update_data().

Signed-off-by: Martin Kurbanov <mmkurbanov at salutedevices.com>
---
 cmd/ubi.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/cmd/ubi.c b/cmd/ubi.c
index 23b6211f6c..b68b51c6a9 100644
--- a/cmd/ubi.c
+++ b/cmd/ubi.c
@@ -363,6 +363,11 @@ static int ubi_volume_continue_write(char *volume, void *buf, size_t size)
 	if (vol == NULL)
 		return ENODEV;
 
+	if (!vol->updating) {
+		printf("UBI volume update was not initiated\n");
+		return EINVAL;
+	}
+
 	err = ubi_more_update_data(ubi, vol, buf, size);
 	if (err < 0) {
 		printf("Couldnt or partially wrote data\n");
@@ -412,6 +417,10 @@ int ubi_volume_begin_write(char *volume, void *buf, size_t size,
 		return -err;
 	}
 
+	/* The volume is just wiped out */
+	if (!full_size)
+		return 0;
+
 	return ubi_volume_continue_write(volume, buf, size);
 }
 
-- 
2.43.0